KR20010068172A - Advanced Electric Oxidaition Process - Google Patents

Abstract

PURPOSE: Provided is a wastewater treatment system using advanced electric oxidation process. In detail, the system can treat non-degradable components and toxic materials in wastewater by adding hydrogen peroxide and ferrous chloride and applying a weak electric current at the same time. CONSTITUTION: The wastewater treatment system consists of the following parts: a reservoir (1); a chemicals tank (8) containing sulfuric acid, hydrogen peroxide, ferrous chloride, sodium hydroxide and coagulants; a first pH adjusting tank (2) equipped with stirrers (10); a reaction tank (3) to treat wastewater through advanced oxidation using Fenton; a second pH adjusting tank (4) to neutralize secondly wastewater by sodium hydroxide; a flocculation tank (5) adding polymer and connected from valves (6a,6b,6c,6d,6e); and an electric current supplier (7).

Description

Wastewater Treatment Apparatus and Method for Fenton Oxidation Treatment Using Electrolysis {Advanced Electric Oxidaition Process}

The present invention relates to a Fenton oxidation treatment method using electrolysis of industrial wastewater, such as livestock wastewater, dyeing wastewater, and landfill leachate, and includes hydrogen peroxide and ferrous chloride in wastewater to efficiently treat hardly decomposable and toxic substances. The development of the Fenton Oxidation Treatment Process (AEOP), which uses electrolysis to treat wastewater by applying a weaker electric charge while applying electricity, reduces the cost of chemicals and improves the efficiency of wastewater purification. In addition, the present invention relates to a wastewater treatment apparatus and a construction method of the Fenton oxidation treatment using the electrolysis invented to prevent the second environmental pollution.

First, the Fenton oxidation reaction and electrochemical decomposition performed in the present invention will be described.

The FENTON oxidation theory was first discovered by Fenton in 1894 that the mixing of divalent iron ions with hydrogen peroxide in acidic conditions produced strong OH radicals. Since then, Haber and Weiss have proposed a theoretical reaction mechanism for this reaction, which is the Haber-Weiss Cycle.

The Haber-Weiss Cycle in the absence of organic matter is mainly a decomposition reaction of hydrogen peroxide, and when organic matter (RH) is present in the wastewater, the reaction occurs in which a substitution product occurs instead of the decomposition reaction because organic matter reacts with OH radicals. . That is, when organic matter is oxidatively decomposed by the Fenton's reagent, iron ions circulate between the divalent and trivalent oxidation states. Fe ²⁺ with the catalytic function is oxidized to Fe ³⁺ by hydrogen peroxide to generate OH radicals, which react with organics to form organic radicals (RH), which then ^converts Fe ³⁺ into Fe ²⁺ Eventually reducing itself to oxidative degradation.

The theory of electrochemical decomposition, the theory of electrochemical decomposition, was established about 180 years ago, and is used in general industrial fields such as hydrogen gas production by electrolysis of water, plating industry, and water treatment using ion exchange membranes. Are on stage. Applications in the wastewater sector require a high degree of electrolysis technology as the wastewater composition, concentration and temperature vary. Electrochemical decomposition is a method of purifying wastewater by causing an electrolysis reaction because electric energy is supplied to wastewater mixed with an inorganic or organic electrolyte. In the electrolysis reaction, high-speed oxidation and reduction (10-13 / sec) are performed continuously to perform oxidation, reduction, decomposition, precipitation, neutralization, coagulation, and sterilization, and electrode reaction and electrode reaction products at the interface between electrode and wastewater The secondary reaction takes place by working with the constituents in the wastewater, and the electrode reaction product separates water and impurities by the action of precipitation, adsorption, flotation, etc. to completely purify the wastewater. When the current flows through the electrode in the electrolytic bath, the reaction occurs at the anode and cathode. Oxidation reaction at the anode and reduction reaction at the cathode. In addition, highly reactive metals (K ⁺ , Ca ²⁺ , Na ⁺ , Mg ²⁺ , Al ³⁺ ‥‥) ions are reduced to water instead of metal at the cathode to generate hydrogen gas. _{^{-, SO 4 -2, PO 4}} 3-, CO 3 - ‥‥) are generated by the oxygen oxidation of the water is not discharged from the anode. Therefore, in the present invention, the Fenton oxidation reaction and electrochemical decomposition are used to treat the hardly decomposable industrial wastewater.

At present, the industrial wastewater of our country is facing the limitation of treatment by the existing activated sludge method only due to the quantitative increase, the hard degradability and the increase rate of the generation of toxic substances.

Fenton oxidation treatment using chemicals, which is one of the wastewater treatment technologies that can efficiently treat these hardly degradable toxic substances, is a good treatment method in which wastewater is treated by the strong oxidation of OH radicals produced by hydrogen peroxide and iron salts. Although showing efficiency, the economic problems of the industrial site due to the high cost of the drug has emerged, the phenomenon of avoiding the application of Fenton oxidation treatment appears, and there was also a problem that the third environmental pollution occurs by using excessive chemicals.

The present invention has been invented in view of the above problems, and the sulfuric acid, hydrogen peroxide, ferrous chloride, hydroxide in the first PH adjusting tank, the reaction tank, the second PH adjusting tank, the flocculating tank through the storage tank to treat the hardly degradable wastewater. A treatment plant capable of treating the wastewater in which sodium and flocculant are added and stirred, respectively, by a highly electrooxidation treatment method in a reaction tank;

The treated water treated by the AEOP in the treatment plant is transferred to the sedimentation tank, and the supernatant is discharged through the discharge tank through the treatment water tank and the carbon filter (A / C Filter), and the precipitated sludge is sent to the concentration tank. As a configuration to be treated, the present invention is a low-cost industrial wastewater by applying hydrogen peroxide and ferrous chloride in the treatment of hardly degradable industrial wastewater and applying electricity to treat the wastewater by advanced electrooxidation method without administering excessive chemicals It is invented to process.

1 is a configuration diagram of the Fenton oxidation treatment using the electrolysis of the present invention.

2 is a block diagram of a Fenton oxidation process using the electrolysis of the present invention.

<Description of Signs for Main Parts of Drawings>

1: storage tank, 2: first PH adjusting tank, 3: reaction tank, 4: second PH adjusting tank,

5: coagulation tank, 6a, 6b, 6c, 6d, 6e: chemical regulating valve, 7: electric applying device,

8: drug tank, 9: PH meta, 10: stirrer, 11: sedimentation tank,

12: treatment tank, 13: carbon filter, 14: discharge tank, 15: concentration tank,

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. The industrial wastewater introduced into the storage tank 1 is a chemical tank (8) containing sulfuric acid (H ₂ SO ₄ ), hydrogen peroxide (H ₂ O 2), ferrous chloride (FeCl ₂ ), sodium hydroxide (NaOH), and a flocculant (8). Valves 6a and 6b to be introduced into the first PH adjusting tank 2, the reaction tank 3, the second PH adjusting tank 4, and the coagulation tank 5, each of which is provided with a stirrer 10; 6c) (6d) (6e) is connected to the pipe, the reactor 3 is equipped with an electrical application device (7) so that the wastewater is subjected to a high electro-oxidation process by Fenton oxidation treatment, A high oxidation oxidation wastewater in the reaction tank (3) is neutralized and adjusted with sodium hydroxide in a second PH adjusting tank (4), and then mixed with a polymer and stirred to coagulate suspended solids (5);

Wastewater aggregated in the coagulation tank 7 is introduced into the settling tank 11 and stabilized, and the precipitated sludge is discharged to the thickening tank 15, and the supernatant water is discharged through the treatment water tank 12 and the carbon filter 13. A wastewater treatment device configured to discharge the wastewater at 14);

While adding sulfuric acid to the wastewater of the first PH control tank (2) introduced from the storage tank (1) while raising the pH of the PH meta (9) to 3 to 4 while stirring with the stirrer (10) to the reaction tank (3) Hydrogen peroxide (H ₂ O ₂ ) and ferrous chloride (FeCl ₂ ) were added to the introduced wastewater, and ferrous chloride was added to the electric application device 7 while maintaining rapid agitation such that the rotation speed of the agitator 10 was 180 rpm. Conduct electricity to the electrolysis so that the wastewater is subjected to the advanced electrooxidation process while checking the PH meta (9);

Sodium hydroxide (NaOH) was added to the second PH adjusting tank 4 in the wastewater subjected to highly electrooxidation by the Fenton oxidation reaction and electrolysis so that the meter of the PH meta (3b) was 7 to 8, and then the coagulation tank ( 5) After adding a flocculant (Polymer), the agitator 10 was slowly stirred at 50 rpm for 20 minutes, and again precipitated in the settling tank 11, and the supernatant water was discharged through the treatment tank 12 and the carbon filter 13. 14), and the precipitated sludge is a wastewater treatment method to be discharged to the concentration tank (15). Reference numerals 10a, 10b, 10c, and 10d are stirrers for mixing with treated water when chemicals are added to each tank, 9a is ORP (oxidation transition) meta, and 9b is installed in the second PH control tank. It is PH meta, and 16 is an air injection nozzle installed in a storage tank, a treatment tank, and a discharge tank to aerated air.

An embodiment of the present invention will be described based on the wastewater treatment apparatus and the construction method configured as described above.

Method of implementation

Fenton oxidation reaction experiment using electrolysis is carried out as follows.

① Adjust PH of raw wastewater (3 ~ 4)

② Oxidation reaction using Fenton reagent

③ Electrolysis using electric energy

④ Neutralization reaction (PH 7-8)

⑤ Experiment in order of flocculation precipitation by adding polymer flocculant.

The sulfuric acid (H ₂ SO ₄ ) piping line valve 6a of the chemical tank 8 is opened to the raw wastewater aerated by air in the storage tank 1 and flowed into the first PH adjusting tank 2 to open the sulfuric acid (H). ₂ SO ₄ ) is added to adjust the pH of the PH meta (9) to 3-4, and then the pH is sent to the reactor (3). In the reactor (3), hydrogen peroxide (H ₂ O ₂ ) and chloride are used as the Fenton reagent. In order to use ferrous iron (FeCl ₂ ), the agitator 10 installed in the center of the reaction tank 3 was rapidly stirred at 180 rpm while opening the valves 6b and 6c of each pipe line and introducing hydrogen peroxide and ferrous chloride. Keep going.

At this time, the organic matter treatment rate by the Fenton oxidation reaction is changed according to the injection amount of hydrogen peroxide, so when the hydrogen peroxide injection amount is small, the organic matter cannot be effectively oxidized. Due to the hydrogen peroxide that remains undecomposed, a high COD value can be displayed, and the opening and closing of the valve 6b is adjusted while observing the treatment efficiency by changing the injection amount of hydrogen peroxide to find an appropriate injection amount of hydrogen peroxide.

In addition, since the organic matter treatment rate is greatly changed by the amount of ferrous chloride injected, the ferrous chloride is introduced by opening the valve 6c after the injection of hydrogen peroxide is finished.

After the hydrogen peroxide and ferrous chloride are added as described above, the voltage is applied to the raw wastewater of the reactor 3 using the electrode of iron, so that the electric oxidation process occurs even after the Fenton oxidation reaction using electricity occurs. Oxidaition Process). In this way, the raw wastewater of the reactor (3) is combined with chemical oxidation and electrolysis to be treated by advanced electrooxidation treatment. The Fenton oxidation reaction generally proceeds within the pH range of 3 to 4, and when the oxidation reaction is completed, iron ²⁺ , Fe ³⁺ ) to increase the pH to remove. Therefore, PH is adjusted in the second PH adjusting tank 4 to neutralize the wastewater. At this time, the valve 6d of the sodium hydroxide pipe line of the chemical tank 8 is opened to open the PH meta (9) gauge. Sodium hydroxide (NaOH) is added to 8.

As described above, when sodium hydroxide is added in the second PH adjustment tank, Fe (OH) ₃ (S) solubility is the lowest at about pH 8, so iron ions are precipitated and removed in most processes as hydroxides.

At this time, a part of the remaining substance in the reaction solution is adsorbed on the iron (III) hydroxide flocculation.

The treated water adjusted to PH 7 to 8 by adding sodium hydroxide was transferred to the coagulation tank 5 to open the valve 6e to add a polymer as a coagulant, and the stirrer 10 was slowly stirred at 50 rpm for 20 minutes. After the stabilization process in the sedimentation tank 11, the flocculated sludge is precipitated, and the upper supernatant is aerated mixed with air again in the treated water tank 12 on one side, and then filtered while passing through a carbon filter (activated carbon) 13 After being discharged by aeration mixed with air again in the discharge tank 14, the sludge precipitated at the bottom of the settling tank 11 is discharged to the concentration tank 15 is transferred to a separate sludge treatment plant.

The experiments on the treatment of livestock wastewater, landfill leachate, and dyeing wastewater in a dyeing plant using the advanced electrooxidation method, as described above, look at Fenton's oxidation treatment using only chemicals and advanced electrooxidation treatments in which a small amount of chemical is applied. As follows.

Experiment 1: Livestock Joint Treatment Plant Wastewater

1) Treatment efficiency according to Fenton chemical injection volume

In general, when performing the Fenton oxidation experiment for the first time, it is recommended that the injection amount of hydrogen peroxide be 0.5 times the COD or BOD of the sample.However, in order to find the optimal condition, the H ₂ O ₂ injection rate is fixed to 500 mg / L. The experiment was performed by changing the hydrogen peroxide / iron salt ratio to 1: 1, 1: 4, 1: 6, 1: 8, 1:10. The polymer flocculant (polymer) was constantly injected at 3 mg / L and the reaction time was 1 hour. After the Fenton oxidation reaction, the COD _Mn concentration of the filtrate was measured using a carbon filter.

As shown in Table 1, the initial CODmn concentration of the livestock co-treatment plant was reduced from 442 mg / L to 4.6 mg / L after the Fenton oxidation, and the COD _Mn concentration was reduced to 87 mg / L and 54 mg / L after passing through the carbon filter, and the hydrogen peroxide / iron salt ratio was 1:10. In the case of organic matter treatment, the efficiency was 87.78%.

In the Fenton oxidation reaction, iron (II) ions act as a catalyst, but they react with the OH radicals in excess of an appropriate amount to consume OH radicals. Therefore, the proper ratio of iron and hydrogen peroxide (Fe ²⁺ / H ₂ O ₂ ) must be selected in order for the iron (II) ion to act as a catalyst, not as a scavenger, so the amount of hydrogen peroxide injected is 1,000 mg / L and the hydrogen peroxide / iron salt ratio Was changed to 1: 2, 1:10, 1:11, 1:12. The experimental results are shown in Table 2 below.

As shown in Table 2, the concentration change according to the chemical injection amount showed that the COD _Mn treatment rate was 91.56% when the hydrogen peroxide / iron salt ratio was 1:10, and the COD _Mn value increased slightly as the iron salt ratio was increased.

In addition, as shown in Table 3 below, the stirring time was 30 and 60 minutes, and the organic matter treatment rate was 87.31% at 30 minutes and 87.04% at 60 minutes. In this experiment, it can be seen that having a Fenton stirring time of 30 to 60 minutes can be expected to have a good treatment rate.

2) Fenton oxidation rate using electrolysis device

In order to select the optimal voltage (V) of the Fenton oxidation reaction, the experiment was performed by fixing the hydrogen peroxide / iron salt ratio to 1: 2 and changing the voltage to 1V, 5V, 10V, and 15V.

Experimental results show that the processing rate of 86.99% at a voltage of 5V as shown in Table 4 below, and using a voltage of 5V or more can increase the temperature of the sample little by little.

In this experiment, the concentration of hydrogen peroxide was fixed at 500 mg / L, 5V was added with an electrolysis device, and the hydrogen peroxide / iron salt ratio was changed to 1: 1, 1: 4, 1: 6, 1: 8, and 1:10. It was. As shown in Table 5 below, when the initial COD _Mn concentration was 456 mg / L to 1:10, the highly electrooxidized water was 68 mg / L, and the concentration of the filtrate was reduced to 25 mg / L after passing through the carbon filter. .

This supplies electric energy into the reaction tank (Fenton oxidation tank), so the Fenton oxidation reaction and the electrolysis reaction are simultaneously performed. Therefore, since Fe electrode is used, Fe ²⁺ elution and oxygen ion generation at the anode, and hydrogen gas and OH ^_ eluted at the time of electrolysis at the cathode have a synergistic effect on the Fenton oxidation reaction.

As a result, comparing the Fenton oxidation treatment using electrolysis with the Fenton oxidation treatment using only chemicals, the organic removal efficiency was about 94.51% in the former case and the 87.78% removal efficiency in the latter case. The organic treatment rate was about 6.78%. Table 6 and Table 7 compare the COD _Mn treatment rates of the conventional Fenton oxidation process with the AEOP process of the present invention.

Experiment 2: Landfill Leachate

1) Characteristics of Raw Leachate

As shown in Table 8 below, the characteristics of the landfill leachate source water can be summarized into two main categories.

First, inflow fluctuations are very large. BOD ₅ is distributed at 540-1,536 mg / L, and CODcr is distributed at 1,557-4800 mg / L, and the difference between the maximum value and the minimum value is about three times.

Second is the presence of high concentrations of reducing nitrogen. The concentration of TKN, which represents the sum of ammonia and organic nitrogen, is very high at 1,086 to 1,214 mg N / L, most of which is ammonia nitrogen.

2) Treatment efficiency according to Fenton chemical injection volume

Fenton's oxidation experiments were conducted using Aerated Lagoon effluent samples and the organic treatment rates were investigated according to reaction time, reaction pH, oxidant injection rate and injection ratio.

According to the landfill leachate data, the ratio of 1: 1.2 to 1,500 mg / L of hydrogen peroxide is recommended as an organic treatment, but in this experiment, the iron salt ratio was fixed at 2,000 mg / L and the iron salt ratio was 1: 1.5, 1: 1.75, 1: 2, 1: 2.5 was changed to the experiment.

Table 9 and Table 10 below show the change in concentration according to the amount injected. In the Fenton oxidation reaction, the organic matter treatment ratio was 2,000 mg / l of hydrogen peroxide and iron salt injection ratio of 1: 1.5. The COD _Mn concentration before the reaction was 800 mg / L, the COD _Mn concentration after the reaction was 250 mg / L, and the filtrate after the carbon filter 173.3 mg / L of organic matter removal was 78.3%.

As described above, the concentration change and the amount of organic matter treatment according to the amount of injection of the drug can be known.

In addition, the organic matter concentration was compared after 30 and 60 minutes to see the effect of the Fenton oxidation time. After 30 minutes, the concentration of COD _Mn was 60%, but due to the residual amount of hydrogen peroxide, bubbles were formed at the stage of iron salt precipitation, which caused the sludge to float. Therefore, the Fenton oxidation reaction time is 60 minutes and the optimal condition is to inject the iron salt ratio 1: 1.5 to the hydrogen peroxide concentration of 2,000mg / L.

3) Fenton treatment efficiency using electrolysis device

As in the Fenton experiment, the iron salt ratio was 1: 1.5 to 2,000 mg / L of hydrogen peroxide, and 5 V of electrical energy was added using an iron electrode after adding the Fenton's reagent. As a result, the organic matter treatment rate was 64.5%. The reason why the treatment rate is lower than the Fenton experiment is believed to be due to the content of Fe in the leachate and Fe ²⁺ ions eluted from the electrode. In addition, it was observed that excessive bubbles were formed by oxidation and reduction reactions through electrical energy, and were floated upward by hydrogen gas.

On the other hand, 5V of electrical energy was added to 2,000 mg / L of hydrogen peroxide without injecting FeCl ₂ . As a result, before reaction COD _Mn concentration is 800mg / L after a reaction COD _Mn concentration COD _Mn concentration of the filtrate that has passed through and 257.4mg / L, a carbon filter is found to 173.3mg / L. The organic treatment rate is 78.3%, which has the same treatment rate as the conventional Fenton oxidation reaction, and the amount of sludge generated is reduced by about 60% compared to the conventional Fenton oxidation reaction.

Therefore, it can be seen that the Fenton oxidation treatment using the electrolysis of the present invention is economically superior in throughput as well as the conventional Fenton oxidation process in landfill leachate.

Experiment 3: Dyeing Wastewater

1) Dyeing wastewater raw water characteristics

The COD of the wastewater and effluent of the dyeing wastewater at the wastewater treatment plant of the dyeing plant during the experiment is shown in Table 11 below.

2) Treatment efficiency according to Fenton chemical injection volume

The injection rate of hydrogen peroxide is fixed at 250mg / L, 500mg / L and 1000mg / L, respectively, and the injection ratio is changed to 0: 0, 1: 1, 1: 3, 1: 5, 1: 6 to determine the optimum injection ratio. It was. Table 12 below shows the change in COD according to the injection ratio.

Referring to Table 12, when the injection amount of hydrogen peroxide was 500 mg / L, the COD decreased from 779 mg / L before treatment to 86-45 mg / L after passing the carbon filter, and the ratio of hydrogen peroxide / iron salt was 1: 6, showing the best treatment rate. .

3) Fenton oxidation and AEOP oxidation efficiency

In this experiment, the hydrogen peroxide injection amount was fixed at 500 mg / L, and the hydrogen peroxide / iron salt ratio was changed to 0: 0, 1: 1, 1: 3, 1: 5, 1: 6 while changing the injection ratio at the same time as the Fenton reaction. Pharmacopoeia was applied to compare the efficiency with previous experimental data.

As can be seen from the above experiments, the following conclusions can be obtained from the comparative experiments using the advanced electro-oxidation method using the conventional Fenton oxidation and electrolysis device.

First: Fenton oxidation treatment of livestock waste water treatment plant cavity is hydrogen peroxide 500mg / L with reference to inject the hydrogen peroxide / ferrous salt (Ⅱ) ratio is 1:10 COD _Mn indicates a throughput of 87.78% under the same conditions AEOP (Advanded Electric Oxidaton Process) Oxidation treatment showed a COD _Mn dmfh dir 94.52% throughput.

Secondly, in landfill leachate, 78.3% of COD _Mn was added in the existing Fenton oxidation treatment with hydrogen peroxide / iron salt (II) ratio 1: 1.5 based on 2,000 mg / L hydrogen peroxide and AEOP oxidation treatment with 2,000 mg / L hydrogen peroxide, respectively. The throughput was shown.

Third: In the dyeing wastewater, the COD _Mn treatment ratio of the Fenton oxidation treatment and the AEOP oxidation treatment injected 1: 3 when the hydrogen peroxide / iron salt (II) ratio was injected 1: 5 based on the hydrogen peroxide 500 mg / L was similar. Had In addition, the injection ratio 1: 1 of hydrogen peroxide 500mg / L showed that the COD _Mn treatment rate of AEOP was about 13.5% higher than that of Fenton's oxidation treatment.

Fourth: Compared with the sludge generation, sludge reduction was found to be 58% for livestock waste, 60% for leachate, and 59% for dyed waste compared to Fenton's oxidation.

As described above, the advanced electro-oxidation method (AEOP) has a superior chemical cost, lower management cost, and higher organic treatment rate than the Fenton oxidation method using only chemicals. There is an effect that can be prevented.

Claims (2)

The industrial wastewater introduced into the storage tank 1 is a chemical tank (8) containing sulfuric acid (H ₂ SO ₄ ), hydrogen peroxide (H ₂ O 2), ferrous chloride (FeCl ₂ ), sodium hydroxide (NaOH), and a flocculant at the top (8). Valves 6a and 6b to be introduced into the first PH adjusting tank 2, the reaction tank 3, the second PH adjusting tank 4, and the coagulation tank 5, each of which is provided with a stirrer 10; 6c) (6d) (6e) is connected to the pipe, the reactor 3 is equipped with an electrical application device (7) so that the wastewater is subjected to a high electro-oxidation process by Fenton oxidation treatment, A high oxidation oxidation wastewater in the reaction tank (3) is neutralized and adjusted with sodium hydroxide in a second PH adjusting tank (4), and then mixed with a polymer and stirred to coagulate suspended solids (5); Wastewater aggregated in the coagulation tank 7 is introduced into the settling tank 11 and stabilized, and the precipitated sludge is discharged to the thickening tank 15, and the supernatant water is discharged through the treatment water tank 12 and the carbon filter 13. A wastewater treatment apparatus for Fenton oxidation treatment using electrolysis, characterized in that the wastewater treatment apparatus is discharged in 14). While adding sulfuric acid to the wastewater of the first PH control tank (2) introduced from the storage tank (1), while raising the pH of the PH meta (9) to 3 to 4 while stirring with the stirrer (10), flows into the reactor (3) Hydrogen peroxide (H ₂ O ₂ ) and ferrous chloride (FeCl ₂ ) were added to the wastewater, and the agitator 10 was rapidly stirred to maintain a rotational speed of 180 rpm. Conduction of electricity to allow electrolysis, and the wastewater is subjected to a highly electrooxidation process while checking the PH meta (9); Sodium hydroxide (NaOH) was added to the second PH adjusting tank 4 in the wastewater subjected to highly electrooxidation by the Fenton oxidation reaction and electrolysis so that the meter of the PH meta (3b) was 7 to 8, and then the coagulation tank ( 5) After adding a flocculant (Polymer), the stirrer 10 was slowly stirred at 50 rpm for 20 minutes and precipitated again in the settling tank 11, and the supernatant water was discharged through the treatment tank 12 and the carbon filter 13 14), and the sewage sludge discharged to the concentration tank 15, the wastewater treatment method of the Fenton oxidation treatment using electrolysis, characterized in that the wastewater treatment.